I want to change default settings of '2d animation'
Color 2 is the world color.

You can set the size of the camera canvas in the render resolution panel (and then use scroll wheel or Ctrl + Middle Mouse Button to scale the view in the 3d window).

Color 1 is a viewport matte with transparency, it can be set going in object mode, selecting the camera, and varying its &quot;passepartout&quot; value.

Then you can go to the file menu, defaults, save startup file, to mantain your settings in any new project.